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Discussion Starter #1
My Farrari Daytona ran out gas and now I can't get it started! Oh yah gas.

Seriously though my Spider had a rely attached to the coil brace. It also had duel pick up distributor that that was changed to a single point set up by the PO.
Question 1: since the wires were snipped, I have been able to find a black wire and a white wire in a black plastic shroud laying near the FI on the right side. The empty rely box is attached to the coil bracket in the same area.
Questioned 2: Will the single point set up cause any lack of power or cause the car to run rich. Would it be better to install a high out put electronic system or put it back to it 's original config?
Thanks.
 

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1966-2013
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I dunno nuthin' about your wires, but as to the rest, in the grander scheme of things and presuming everything is in top shape, a dual point setup will perform a bit better than a single point rig (relevant to control of dwell time and such) and an electronic rig will better either.

An electronic with programmed/programmable advance curve will be potentially more accurate than an electronic that's flyweight advanced, and many feel that a electronic with programmed/programmable advance that uses a crank position pickup ('60-2 crank pulley gear') will be better than a electronic programmed/programmable setup that utilizes a magnetic or optic device inside the dizzy body to fire the coil.
(and magnetic is seemingly preffered over optic in that scenario, 'cause magnets work even if dirty while optics don't)

Stock look in an electronic with adjustable advance curve would be in something like the 1-2-3 dizzy setup.
Non-stock looking would be a crank wheel and pickup and something like a Ford EDIS ignition, program box and 4 coil pack.

Or you can rebuild/replace the stock points dizzy with good bushings, flyweights, etc. and have someone tweak the curve a bit for you if desired, pop it in and prolly be just as happy with that as any of the other options unless you are heavily performance orientated. Just have to keep the points proprly gapped and put a drop of oil on the innards once in a while to keep them free and to help prevent wear.

Doubtful a single point rig will cause rich running over any other option, provided its set properly in dwell, point gap and actual timing, the condensor is in good working order, and the rest in good mechanical order in regard to the flyweights, cap, rotor and shaft fitment in the body/bushings.
ie: if everything is right, there should be no decernable difference other than perhaps a bit less go in the upper rpm ranges.

How's that for all the answer you prolly didn't want to see :D
 

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...a dual point setup will perform a bit better than a single point rig...
In a V8 application, yes. The reason is coil saturation time. At, say, 5000RPM, the points are opening 20,000 times per minute. This may reduce coil saturation time to the point that a high speed ignition misfire may occur. Adding a second set of points, slightly offset from the first, allows the dwell angle to be increased which increases saturation time. This reduces the chance of a high speed misfire.

A 4 cylinder running at 5000RPM does not have this problem as the points are opening only 10,000 times per minute. The purpose for the dual point in the Alfa application is for starting, emissions and knock prevention (depending on the year). Using two sets of points, set about 3-ish degrees apart, allows the ignition timing to be changed by a like amount depending on which set of points is being used. Unlike the V8 dual points which uses both points at the same time, the Alfa uses only one set at a time.
 

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papajam said:
the Alfa uses only one set at a time.
Well ain't that sumpthin'.

As both sets of points run on the same eccentric, how is it determined which set will be doing the work at a given time.
I mean there's not like a switch somewhere that says 'set A til X, then set B from then on' is there? (or is there?)
As in how does it know which set to use under a given circumstance?
 

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Yep. There's a switch alright. Some applications use a vacuum switch which, under high engine load (low vacuum), switches to the retard set of points to prevent knock. Another application (77 I think) uses a coolant temp sensor to switch between points sets.
 

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Discussion Starter #7
Dual vs single points

Well Papjam & Tifosi thanks for the replies and the lessons. My car runs fairly well and is very reliable as is. I have this nagging feeling if I mess with the points/distributor with my limited knowledge I'm asking for unneeded and unwanted problems. So I'll leave it as is for now or at least until the kids college is paid.
 
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